Electro-magnetic lens, charged particle beam transferring apparatus, and method for manufacturing electro-magnetic lens
AssigneeNikon Corporation
InventorMamoru Nakasuji
Life of this patent
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Abstract
A charged particle beam transferring apparatus includes a pair of electro-magnetic lenses spaced apart in the direction of the optical axis. Each electro-magnetic lens consists of a coil and core made of magnetic material and having two magnetic poles. The core of at least one of the electro-magnetic lenses is made of ferrite. An insulating member supports the two magnetic poles of the core of the at least one of the electro-magnetic lenses between its two magnetic poles.
Claims25
An electro-magnetic lens comprising:
- a coil;
- a core made of ferrite and having two magnetic poles, said coil being received by said core;
- and an electrically insulating support member disposed between said coil and an optical axis of the lens to support said magnetic poles.
An electro-magnetic lens comprising:
- a coil;
- and
- a core made of ferrite and having two magnetic poles, said core having a surface-smoothing layer made of ferromagnetic material disposed on a surface portion thereof and which is effective to suppress magnetic flux irregularities due to lack of smoothness of said surface portion.
A charged particle beam transferring apparatus comprising:
- a pair of electro-magnetic lenses spaced apart in a direction of an optical axis, for emitting charged particle beams from a mask to a substrate, each of said electro-magnetic lenses comprising a coil and a core made of a magnetic material and having two magnetic poles, said core of at least one of said electro-magnetic lenses being made of ferrite and having a surface-smoothing layer of ferromagnetic material disposed on a surface portion thereof and which is effective to suppress magnetic flux irregularities due to lack of smoothness of said surface portion.
A charged particle beam transferring apparatus comprising:
- an electro-magnetic lens for emitting charged particle beams from a mask to a substrate and including a core made of ferrite and having two magnetic poles, and said core having a surface-smoothing layer made of ferromagnetic material on a surface portion thereof and which is effective to suppress magnetic flux irregularities due to lack of smoothness of said surface portion.
A method for manufacturing an electromagnetic lens, comprising:
- bonding a surface-smoothing layer made of a ferromagnetic material on a surface portion of a core, made of ferrite and having two magnetic poles, through an adhesive;
- and
- attaching a coil to the core on which said layer is formed,
- said surface-smoothing layer being effective to suppress magnetic flux irregularities due to lack of smoothness of said surface portion.
A method of manufacturing an electro-magnetic lens, comprising:
- forming a thin film surface-smoothing layer made of a ferromagnetic material on a surface portion of a core made of ferrite and having two magnetic poles by at least one of the methods of plating, vacuum evaporation, deposited injection, ion beam evaporation, sputtering, and reactive sputtering;
- and
- attaching a coil to the core on which said layer is formed,
- said surface-smoothing layer being effective to suppress magnetic flux irregularities due to lack of smoothness of said surface portion.
Dependencies are inferred from the claim text.